Open AccessFrequency tracking loop with wide pull‐in range for weak DSSS signal
Author(s) -
Guo Yichao,
Huan Hao,
Tao Ran,
Wang Yue
Publication year - 2018
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2018.6631
Subject(s) - direct sequence spread spectrum , discriminator , frequency offset , spread spectrum , chirp spread spectrum , bandwidth (computing) , process gain , phase locked loop , computer science , delay locked loop , control theory (sociology) , loop (graph theory) , residual , offset (computer science) , electronic engineering , engineering , jitter , telecommunications , algorithm , mathematics , channel (broadcasting) , detector , artificial intelligence , control (management) , combinatorics , orthogonal frequency division multiplexing , programming language
A frequency tracking loop based on triangle function frequency discriminator and adaptive loop bandwidth adjustment is proposed to track the Doppler frequency of weak direct‐sequence spread spectrum (DSSS) signal. The proposed structure first provides a frequency discrimination with wide pull‐in range to lock the large residual frequency offset after acquisition. Then, the adaptive loop bandwidth adjustment is employed to improve the accuracy of frequency estimation. Compared with the conventional tracking loop, the proposed structure has wider pull‐in range and higher sensitivity. Simulation results verify the validity of the proposed method.